Free Implied Odds Calculator
Enter your betting odds in any format to instantly calculate implied probability, fair decimal odds, potential payouts, and break-even stakes. Our calculator handles American (+/-), Decimal, and Fractional odds with precision. Whether you're comparing parlay betting strategies or evaluating individual bets, understanding implied probability is crucial for finding value.
Quick Conversion Reference
| Probability | Decimal | American | Fractional |
|---|---|---|---|
| 50% | 2.00 | +100 | 1/1 |
| 40% | 2.50 | +150 | 3/2 |
| 33.33% | 3.00 | +200 | 2/1 |
| 66.67% | 1.50 | -200 | 1/2 |
How to Use the Implied Odds Calculator
Step-by-Step Guide
- Select Your Odds Format: Choose between American (+/-), Decimal, or Fractional odds from the dropdown menu.
- Enter Your Odds: Input the odds exactly as shown by your sportsbook. For American odds, include the + or - sign.
- Add Stake (Optional): Enter your bet amount to calculate potential payout and profit.
- Set Target Payout (Optional): Enter your desired payout to find the required stake amount.
- Calculate: Click the calculate button to see implied probability, fair odds, and all conversions.
- Try Examples: Use the quick example buttons to see the calculator in action with pre-filled values.
Understanding the Results
- Implied Probability: The likelihood of the outcome as suggested by the odds, including bookmaker margin.
- Fair Decimal Odds: The true odds based on implied probability without bookmaker vig.
- Odds Conversions: Your odds displayed in all three formats for easy comparison.
- Potential Payout: Total return including your original stake (shown when stake is entered).
- Profit Amount: Net profit excluding your original stake.
- Required Stake: Amount needed to bet to achieve your target payout (shown when target is entered).
Example Calculations Explained
Example 1: American Odds +150 with $100 Stake
- Implied Probability: 100 / (150 + 100) = 40%
- Decimal Odds: (150/100) + 1 = 2.50
- Potential Payout: $100 × 2.50 = $250
- Profit: $250 - $100 = $150
Example 2: Decimal Odds 3.20 with $50 Stake
- Implied Probability: 1 / 3.20 = 31.25%
- American Odds: (3.20 - 1) × 100 = +220
- Potential Payout: $50 × 3.20 = $160
- Profit: $160 - $50 = $110
Example 3: Fractional Odds 7/2 with $10 Stake
- Decimal Conversion: (7/2) + 1 = 4.5
- Implied Probability: 1 / 4.5 = 22.22%
- Potential Payout: $10 × 4.5 = $45
- Profit: $45 - $10 = $35
Complete Guide to Implied Probability in Betting
What is Implied Probability?
Implied probability is the conversion of betting odds into a percentage that represents the likelihood of an outcome occurring. It's called "implied" because it includes the bookmaker's profit margin (vig or juice) on top of the true probability. Understanding implied probability is the foundation of finding best betting strategies.
For example, if a sportsbook offers odds of 2.00 (even money) on a coin flip, the implied probability is 50%. However, if they offer 1.91 on both heads and tails, each side has an implied probability of 52.36%, totaling 104.72% - the extra 4.72% is the bookmaker's margin.
How to Calculate Implied Probability from Different Odds Formats
American Odds to Implied Probability
For Positive Odds (+150):
- Formula: Implied Probability = 100 / (American Odds + 100)
- Example: 100 / (150 + 100) = 100 / 250 = 0.40 = 40%
For Negative Odds (-200):
- Formula: Implied Probability = -American Odds / (-American Odds + 100)
- Example: 200 / (200 + 100) = 200 / 300 = 0.6667 = 66.67%
Decimal Odds to Implied Probability
- Formula: Implied Probability = 1 / Decimal Odds
- Example: 1 / 2.50 = 0.40 = 40%
- Example: 1 / 1.50 = 0.6667 = 66.67%
Fractional Odds to Implied Probability
- Step 1: Convert to decimal: (Numerator / Denominator) + 1
- Step 2: Calculate probability: 1 / Decimal Odds
- Example: 7/2 → (7/2) + 1 = 4.5 → 1/4.5 = 22.22%
- Example: 1/2 → (1/2) + 1 = 1.5 → 1/1.5 = 66.67%
Fair Odds vs Implied Odds: Understanding the Difference
Fair odds (also called true odds) represent the actual probability of an event without any bookmaker margin. Implied odds include the bookmaker's profit margin, making them slightly less favorable to bettors. This is where understanding implied probability in sports betting becomes essential.
Calculating Fair Odds
To find fair odds, you need to remove the vig from the implied probability:
- Calculate implied probability for all outcomes
- Sum the probabilities (will exceed 100%)
- Divide each probability by the total to normalize
- Convert back to odds: Fair Decimal Odds = 1 / Normalized Probability
Example: NFL Point Spread
- Team A -110 (1.91): Implied probability = 52.36%
- Team B -110 (1.91): Implied probability = 52.36%
- Total: 104.72% (4.72% is the vig)
- Fair probability for each: 50% (52.36% / 104.72% × 100)
- Fair odds: 2.00 (1 / 0.50)
Using Implied Probability to Find Value Bets
The key to profitable betting is finding situations where your assessed probability of an outcome is higher than the implied probability from the odds. This strategy requires mastering how to calculate parlay payouts when combining multiple bets.
Value Betting Formula
Expected Value (EV) = (Your Probability × Decimal Odds) - 1
Example: Finding Value
- Sportsbook offers: Team A at 2.50 (40% implied probability)
- Your analysis: Team A has 50% chance of winning
- EV = (0.50 × 2.50) - 1 = 1.25 - 1 = 0.25 = +25% EV
- This is a value bet! Your probability exceeds implied probability
When NOT to Bet
- Sportsbook offers: Team B at 1.80 (55.56% implied probability)
- Your analysis: Team B has 50% chance of winning
- EV = (0.50 × 1.80) - 1 = 0.90 - 1 = -0.10 = -10% EV
- Avoid this bet! Implied probability exceeds your assessment
Implied Probability in Different Sports
Football (Soccer) Betting
Three-way markets (Win-Draw-Win) typically show higher vig than two-way markets. Learn more about soccer betting to maximize your returns:
- Home Win: 2.20 (45.45%)
- Draw: 3.40 (29.41%)
- Away Win: 3.20 (31.25%)
- Total: 106.11% (6.11% vig)
Basketball Point Spreads
Typically offered at -110 (1.91) on both sides. Discover NBA betting strategies that capitalize on line movements:
- Each side: 52.36% implied probability
- Total: 104.72% (4.72% vig)
- Fair probability: 50% each side
Tennis Match Betting
Two-way markets with varying vig based on match competitiveness:
- Favorite: 1.50 (66.67%)
- Underdog: 2.60 (38.46%)
- Total: 105.13% (5.13% vig)
Advanced Implied Probability Strategies
Line Shopping with Implied Probability
Compare implied probabilities across sportsbooks to find the best value:
- Sportsbook A: Team X at 2.40 (41.67% implied)
- Sportsbook B: Team X at 2.50 (40% implied)
- Better value: Sportsbook B (lower implied probability = better odds)
Closing Line Value (CLV)
Compare your bet's implied probability to the closing line:
- You bet at 2.50 (40% implied probability)
- Closing line: 2.20 (45.45% implied probability)
- Positive CLV: You got better odds than the market settled on
Arbitrage Opportunities
When combined implied probabilities across sportsbooks total less than 100%, you have an arbitrage opportunity. Combine this knowledge with our arbitrage calculator tool to identify guaranteed profits:
- Sportsbook A: Team X at 2.10 (47.62%)
- Sportsbook B: Team Y at 2.15 (46.51%)
- Total: 94.13% (5.87% guaranteed profit opportunity)
Common Mistakes to Avoid
Ignoring the Vig
Many bettors forget that implied probability includes bookmaker margin. Always calculate fair odds to understand true value.
Overestimating Your Edge
Be honest about your probability assessments. Consistently overestimating your edge leads to negative EV betting.
Not Comparing Across Sportsbooks
Different bookmakers offer different odds. A 2-3% difference in implied probability significantly impacts long-term profitability. Use our odds comparison tool to always find the best value.
Betting Without Calculating EV
Never place a bet without first calculating whether it has positive expected value based on your probability assessment.
Tools to Enhance Your Betting Strategy
Combine our Implied Odds Calculator with other professional betting tools:
- Arbitrage Calculator - Find guaranteed profit opportunities across sportsbooks
- Hedge Bet Calculator - Lock in profits or minimize losses on existing bets
- Parlay Calculator - Calculate combined odds and implied probability for multiple bets
- Fibonacci Calculator - Implement progressive staking strategies
- No Vig Calculator - Remove bookmaker juice to find fair odds
- All Betting Tools - Access our complete suite of professional calculators
Professional Betting Tips
- Always calculate implied probability before placing any bet
- Compare odds across multiple sportsbooks to find the lowest implied probability
- Track your probability assessments to improve accuracy over time
- Focus on positive EV bets where your probability exceeds implied probability
- Understand the vig varies by sport, market, and sportsbook
- Use closing line value as a measure of your betting skill
- Maintain detailed records of odds, implied probabilities, and outcomes
Frequently Asked Questions About Implied Odds
To calculate implied probability: For Decimal odds, divide 1 by the decimal odds (1/2.50 = 40%). For American odds, if positive use 100/(odds+100), if negative use -odds/(-odds+100). For Fractional odds like 7/2, convert to decimal first: (7/2)+1 = 4.5, then 1/4.5 = 22.22%. Our calculator handles all conversions automatically.
Implied probability is the likelihood of an outcome occurring as suggested by the betting odds. It represents the bookmaker's assessment of probability plus their profit margin (vig). For example, odds of 2.00 (even money) imply a 50% probability of the event occurring. Understanding implied probability helps you identify value bets where your assessment differs from the bookmaker's.
For positive American odds (+150): Implied Probability = 100 / (150 + 100) = 40%. For negative American odds (-200): Implied Probability = 200 / (200 + 100) = 66.67%. The formula changes based on whether the odds are positive or negative. Our calculator handles both conversions instantly and shows you the results in all formats.
Fair odds (true odds) represent the actual probability without bookmaker margin. Implied odds include the bookmaker's vig/juice. For example, a 50% probability event should have fair odds of 2.00, but bookmakers might offer 1.91, creating implied probability of 52.36% - the difference is their profit margin. Understanding this difference is crucial for finding value bets.
A value bet exists when your assessed probability of an outcome is higher than the implied probability from the odds. Calculate Expected Value (EV) = (Your Probability × Decimal Odds) - 1. If EV is positive, it's a value bet. For example, if you assess 50% probability but odds imply 40%, you have a +25% EV bet. Consistently finding positive EV bets is the key to long-term profitability.
The vig (vigorish) or juice is the bookmaker's profit margin built into the odds. It's why the combined implied probabilities of all outcomes exceed 100%. For example, if both sides of a bet are offered at -110 (52.36% implied each), the total is 104.72% - the extra 4.72% is the vig. Lower vig means better value for bettors.
American to Decimal: If positive, (odds/100)+1. If negative, (100/-odds)+1. Decimal to American: If ≥2.00, (decimal-1)×100. If <2.00, -100/(decimal-1). Fractional to Decimal: (numerator/denominator)+1. Our calculator performs all conversions instantly, showing your odds in all three formats simultaneously.
Closing Line Value measures whether you got better odds than the final line before an event starts. If you bet at 2.50 (40% implied) and the closing line is 2.20 (45.45% implied), you have positive CLV. Consistently achieving positive CLV is a strong indicator of long-term betting profitability, as it shows you're beating the market's final assessment.
Implied probabilities exceed 100% because they include the bookmaker's profit margin (vig). For example, a coin flip should be 50/50 (100% total), but bookmakers might offer 1.91 on both sides (52.36% each = 104.72% total). The extra 4.72% is their guaranteed profit margin. This overround ensures bookmakers profit regardless of the outcome.
Yes, you can calculate implied probability for each leg of a parlay individually. However, for combined parlay odds and payouts, use our dedicated dedicated parlay calculator. It multiplies the decimal odds of each leg and calculates the combined implied probability, which helps you understand the true difficulty of hitting multi-leg parlays.
Implied odds in sports betting refer to the probability suggested by betting odds. Pot odds are a poker concept comparing the current pot size to the cost of a call. While both involve probability calculations, they're used in different contexts. In sports betting, focus on comparing implied probability to your assessed probability to find value bets.
Bookmaker implied probabilities are generally very accurate, especially for major markets with high liquidity. They aggregate information from thousands of bettors and professional models. However, they include vig and can occasionally misprice events, especially in niche markets or when new information emerges. Finding these mispricings is the essence of value betting.